i have problem to send email in odoo 8 i dont know it is for the configure or problems from server

 raise MailDeliveryException(_("Mail Delivery Failed"), msg)

MailDeliveryException: (u'Fallo de entrega de correo', u"La entrega de correo fall\xf3 v\xeda el servidor SMTP 'mail.miditec.com.mx'.\nSMTPSenderRefused: 550\nVerification failed for <postmaster-odoo@cfd>\nThe mail server could not deliver mail to postmaster-odoo@cfd. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.\nSender verify failed\npostmaster-odoo@cfd@miditec.com.mx"